FUNCTION AND THE PATIENT WITH CHRONIC LOW-BACK-PAIN

Objective: To undertake a comparative examination of the reliability a nd validity of two frequently used self-report measures of functional disability, the Pain Disability Index (PDI) and the Oswestry Low Back Pain Disability Questionnaire (OLBPDQ). Design: A descriptive ex-post facto design was used in the study. Setting: Pain clinics and neurosur gical units at three metropolitan hospitals. Subjects: One hundred pat ients with chronic low back pain of noncancer origin were administered the two questionnaires as part of a larger questionnire battery. Resu lts: Acceptable internal consistency values of 0.76 for the PDI and 0. 71 for the OLBPDQ were obtained. A correlation of r = 0.63 was found b etween the PDI and the OLBPDQ, supporting the concurrent validity of t he two scales. Both the scales were found to be correlated to the Beck Depression Inventory scores (PDI, r = 0.42; OLBPDQ, r = 0.39), with h igher disability associated with greater depression. Only the total PD I score was found to be sensitive to functional status differences wit hin the patient sample. Conclusions: These findings support other rece nt work in favor of the PDI. The PDI had a slightly higher internal co nsistency and was more sensitive than the OLBPDQ.